Modified Mohr‐Coulomb – Rankine material model for concrete

Abstract

Purpose -The main aim of this paper is to present a three-dimensional numerical material model for concrete which combines plasticity with a classical orthotropic smeared crack formulation. A further aim is to raise a discussion leading to the creation of a comprehensive computer programme for the analyses of reinforced and prestressed concrete structures. Design/methodology/approach -A new numerical material model for concrete is developed and main theoretical explanations are given to aid in understanding the algorithm. The model is based on Mohr-Coulomb criterion for dominant compression and Rankine criterion for dominant tension influences. A multi-surface presentation of the model is implemented which permits the rapid convergence of the mathematical procedure. The model includes associated and non-associated flow rules, strain hardening and softening where the development of the plastic strain was described by the function of cohesion. Findings -Provides information about developing a new numerical material model for concrete. Practical implications -The model is implemented into the computer programme PRECON3D for the three-dimensional nonlinear analysis of the reinforced and prestressed concrete structures. Originality/value -In this model, the very complex behaviour of concrete is defined by elementary material parameters which can be obtained by a standard uniaxial test. The presented model enables a very detailed and precise analysis of reinforced and prestressed concrete structures until crushing with a high accuracy, so that the expensive experimental tests can be reduced. The paper could be very valuable to researchers in this field as a benchmark for their analyses.

Parametric analysis of constant‐moment zone length in four point bending of reinforced concrete beams

“…As the developed model [11,12] enables a very detailed and precise analysis of reinforced concrete structures until crushing with a high accuracy, we hope to confirm Fantilli et al [10] results what could lead to the improvement of the Eurocode 2 [13] where the size effect on the structural response of compressed concrete is not taken into account.…”

“…[11,12] while here, due to the better understanding of the proposed material model, only a part of the model considering behaviour in compression will be presented in detail.…”

“…In this paper, the nonlinear behaviour of concrete is described by an elastoplastic modified material model which is based on the Mohr-Coulomb law for dominant compression stresses and the Rankine law for dominant tensile stresses [11,12]. A multi-surface presentation of the model is implemented which permits the rapid convergence of the mathematical procedure, Fig.…”

“…7. [9]: static conditions, geometrical characteristics and numerical discretisation for the programme PRECON3D [11,12].…”

“…This model combines plasticity with a classical orthotropic crack formulation [11,12]. The model is defined by elementary material parameters (Young's modulus of elasticity, Poisson's ratio, maximal uniaxial tensile and compression stresses, coefficient of tensile correction, maximal tensile and maximal compression strains) which can be obtained by a standard uniaxial test.…”